Dr. Christina Cifra?s goal is to become an independent investigator and leader in diagnostic safety research focused on preventing diagnostic error-related harm in critically ill children. Dr. Cifra?s career development plan incorporates mentored research and training in advanced epidemiology and biostatistics, qualitative/mixed methods research, and communication to improve diagnostic performance. She will be mentored by a team of experienced investigators with expertise in epidemiological and qualitative investigation of patient safety prob- lems and specific proficiency in diagnostic safety and communication. Dr. L. Herwaldt (primary mentor) is an accomplished epidemiologist with an established record of mentoring successful young investigators. Dr. H. Singh is an internationally known pioneer in pediatric diagnostic safety research with specific expertise in com- munication to improve diagnosis. Dr. H. Reisinger is a medical anthropologist with expertise in mixed methods research. Dr. J. Dawson is a proficient biostatistician who has collaborated on a wide variety of federally- funded biomedical research. Dr. Cifra works in an environment extremely supportive of her success and has access to all of the resources required to achieve her goals. Diagnostic errors (DEs) are a major source of healthcare-associated harm in critically ill children. However, a large gap in our understanding of the diagnostic process on admission to the Pediatric Intensive Care Unit (PICU) prevents the development of targeted strate- gies to prevent DE-related harm. To address this gap, Dr. Cifra proposes a mixed methods study with the ob- jective of developing a PICU-specific conceptual model of referral communication as an integral part of the PICU diagnostic process. She will achieve this by: 1) determining the prevalence of DE in the first 12 hours after non-elective admission to the PICU and patient, provider, and work system characteristics associated with DE, and 2) examining how the manner and content of referral communication between referring clinicians and accepting PICU physicians affect the PICU diagnostic process on admission. For quantitative Aim 1, Dr. Cifra will conduct a retrospective cohort study using structured chart reviews and a validated tool to identify DEs in patients admitted to 2 tertiary referral academic PICUs. For qualitative Aim 2, Dr. Cifra will conduct fo- cused ethnography (observation, interviews, and document review) at the University of Iowa PICU to examine how referral communication affects the PICU diagnostic process on admission. Quantitative and qualitative results will be integrated, producing a novel PICU-specific conceptual model of referral communication and its role in the diagnostic process on PICU admission. The proposed research is innovative in its integrated multi- disciplinary mixed methods approach. Results will be significant, generating hypotheses for future diagnostic safety research and providing information to prevent DE-related harm in children, an AHRQ priority population. This work will provide the foundation for Dr. Cifra?s planned R01 application to develop and test these interven- tions, accelerating her progress towards independence.